比较分析丹参中三个编码对羟苯丙酮酸还原酶的 SmHPPR 基因。

Comparative analysis of three SmHPPR genes encoding hydroxyphenylpyruvate reductases in Salvia miltiorrhiza.

机构信息

Key Laboratory of the Ministry of Education for Medicinal Resources and Natural Pharmaceutical Chemistry, College of Life Science, Shaanxi Normal University, Xi'an 710062, China.

出版信息

Gene. 2024 Jan 20;892:147868. doi: 10.1016/j.gene.2023.147868. Epub 2023 Oct 3.

DOI:10.1016/j.gene.2023.147868

PMID:37797780

Abstract

Hydroxyphenylpyruvate reductase (HPPR) is an enzyme that is involved in the biosynthesis of hydrophilic phenolic acids in Salvia miltiorrhiza, which is a model medicinal plant. Three SmHPPR genes have been identified in the S. miltiorrhiza genome; however, only one has been functionally analyzed. Here, we cloned three SmHPPR genes (SmHPPR1, SmHPPR2, and SmHPPR3) from the cDNA of S. miltiorrhiza, and their expression profiles were studied. The expression levels of SmHPPR1 were significantly higher than those of SmHPPR2 and SmHPPR3, where SmHPPR1 revealed the highest level in stems, while SmHPPR2 and SmHPPR3 exhibited the highest level in flowers. SmHPPR1, SmHPPR2, and SmHPPR3 are localized in the cytoplasm. All three recombinant enzymes had HPPR activities and catalyzed the reduction of 4-hydroxyphenylpyruvic acid (pHPP) to 4-hydroxyphenyllactic acid (pHPL), with SmHPPR1 showing the highest activity. The transient over-expression of SmHPPR1, SmHPPR2, and SmHPPR3 in the leaves of Nicotiana benthamiana promoted the production of pHPL, which indicated that all three SmHPPRs had in vivo activities. Overall, between the three homologs, SmHPPR1 plays a dominant role in catalyzing pHPP to pHPL, which provides new insights into the biosynthesis of phenolic acids in S. miltiorrhiza.

摘要

4-羟基苯丙酮酸还原酶（HPPR）是参与丹参亲水性酚酸生物合成的一种酶，丹参是一种模式药用植物。在丹参基因组中已鉴定出三个 SmHPPR 基因；然而，只有一个进行了功能分析。在这里，我们从丹参 cDNA 中克隆了三个 SmHPPR 基因（SmHPPR1、SmHPPR2 和 SmHPPR3），并研究了它们的表达谱。SmHPPR1 的表达水平明显高于 SmHPPR2 和 SmHPPR3，其中 SmHPPR1 在茎中表达水平最高，而 SmHPPR2 和 SmHPPR3 在花中表达水平最高。SmHPPR1、SmHPPR2 和 SmHPPR3 定位于细胞质中。三种重组酶均具有 HPPR 活性，并催化 4-羟基苯丙酮酸（pHPP）还原为 4-羟基苯乳酸（pHPL），其中 SmHPPR1 表现出最高的活性。SmHPPR1、SmHPPR2 和 SmHPPR3 在烟草原生质体中的瞬时过表达促进了 pHPL 的产生，这表明这三种 SmHPPR 均具有体内活性。总体而言，在这三个同源物中，SmHPPR1 在催化 pHPP 转化为 pHPL 中起主导作用，这为丹参中酚酸的生物合成提供了新的见解。